The All Mountain Adult Workshop is probably a good fit for what you are looking for. Since there is a ski off to split people into ability groups, you shouldn't end up over your head.

Note that when I did the Workshop the day after arrival, I hadn't had time to acclimate to the altitude enough. So I was pretty tired by late afternoon and opted to skip the last 30 min. The snow was deep enough where we went that I was working reasonably hard given how well I skied back then. So you might want to wait until the second ski day.

First day will be at Snowbird, since that's where we're lodging, so that's easy enough. Thanks!

Also, Alta has been described as a half-pipe (steep faces, flat middle.) Typically, the stuff in the center of the two half pipes (~Collins lift, Sugarloaf lift), are the safest to start poking around. But there are some gulleys in there and stay away from Glory Hole. (Actual name.)